Sleep enhancement in an hvac system

ABSTRACT

Methods, controllers, and the like are disclosed that can include determining an occurrence of an event (where the occurrence of the event is determined by a controller of a heating, ventilation, and air conditioning (HVAC) system, and the HVAC system controls a temperature of air in an environment by controlling a setpoint temperature of conditioned air provided by the HVAC system to the environment). Such methods, controllers, and the like can further include, in response to a determination that the event has occurred, altering the temperature of the air in the environment by executing a sleep profile, where the sleep profile is executed by the controller and execution of the sleep profile adjusts the setpoint temperature as a function of time over a time period, such that the temperature of the air in the environment leads an occupant in the environment into a sleep state or a wakeful state.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. Non-Provisional applicationSer. No. 15/699,778, filed Sep. 8, 2017 entitled “SLEEP ENHANCEMENT INAN HVAC SYSTEM” and claims the benefit of and priority to U.S.Provisional Application Ser. No. 62/385,589 entitled “SLEEP ENHANCEMENTIN AN HVAC SYSTEM” filed Sep. 9, 2016, the entirety of which are herebyincorporated by reference herein for all purposes.

BACKGROUND 1. Technical Field

The present disclosure is directed to HVAC controllers, and inparticular, to an HVAC controller that provides an altered temperatureenvironment.

2. Background of Related Art

Heating, ventilation, and air conditioning (HVAC) systems are typicallycontrolled by a thermostat mounted on a wall that enables occupants toset the desired temperature in the building. In summer months, thethermostat can be placed in a cooling mode to operate air conditioningequipment, while in the winter months the thermostat can be placed in aheating mode to operate an oil- or gas-fired furnace, an electricheater, or a heat pump. Many thermostats include an energy-savingscheduling function to enable automatic adjustments of temperature basedon time-of-day, day-of-week, or even seasonally. Some thermostatsinclude occupancy sensing functions that reduce system output duringperiods when no people are present in the building.

Increasingly, the stresses and habits of modern life negatively impact aperson's sleep. People who heavily rely on cell phones exhibit anincrease in sleep disorders and depressive symptoms. Habitual late nightcomputer, smart phone, and tablet use is associated with sleepdisorders, stress and depressive symptoms, and loss of efficiency duringwaking hours. Consequently, many people are increasingly unable toachieve the duration and quality of sleep that they need.

Some thermostats and HVACs include a nighttime “sleep” setback mode,which simply lowers (during winter) or raises (during summer) thesetpoint temperature during sleeping hours to save energy. One drawbackof such simple nighttime setback modes is that they disrupt a person'scircadian rhythms and can impair both the duration and quality of sleep.A thermostat which enhances a person's sleep in an effective andeasy-to-use manner would be a welcome advance.

SUMMARY

The present disclosure describes methods, controllers, and the like foroperating an HVAC system. Such methods, controllers, and the like cancomprehend, for example, determining an occurrence of an event (wherethe occurrence of the event is determined by a controller of a heating,ventilation, and air conditioning (HVAC) system, and the HVAC systemcontrols a temperature of air in an environment by controlling asetpoint temperature of conditioned air provided by the HVAC system tothe environment). Such a method can further include, in response to adetermination that the event has occurred, altering the temperature ofthe air in the environment by executing a sleep profile, where the sleepprofile is executed by the controller and execution of the sleep profileadjusts the setpoint temperature as a function of time over a timeperiod, such that the temperature of the air in the environment leads anoccupant in the environment into a sleep state or a wakeful state.

In some embodiments, the determining the occurrence of the eventcomprises receiving a signal at the controller, where the signal isreceived from a device communicatively coupled to the controller and thesignal indicates detection of the event by the device.

In some embodiments, the determining is performed by a sleep onsetdetermination module of the controller, the event is a sleep onsetevent, the signal is a sleep onset signal, the device sends the sleeponset signal to the controller upon detection of the sleep onset event,and the execution of the sleep profile is caused by the sleep onsetdetermination module processing the sleep onset signal.

In some embodiments, such methods, controllers, and the like caninclude, for example, performing a learning process (where the learningprocess comprises recording the sleep onset event as a recorded sleeponset event and the recorded sleep onset event is one of a plurality ofrecorded sleep onset events recorded as part of the learning process),and updating a schedule (where the schedule is updated using a result ofthe learning process and the schedule is maintained by a schedulingmodule of the controller).

In some embodiments, such methods, controllers, and the like caninclude, for example, detecting the sleep onset event, where thedetecting the sleep onset event comprises receiving one or moreenvironmental conditions of the environment from one or more sensors anddetermining occurrence of the sleep onset event based, at least in part,on the one or more environmental conditions.

In some embodiments, the controller is a thermostat, the HVAC systemcomprises the device and the thermostat, the device is one of aplurality of devices, and each of the plurality of devices monitors oneor more environmental parameters by virtue of comprising one or more ofa temperature sensor, a humidity sensor, a light sensor, a proximitysensor, a thermal imaging sensor, a motion sensor, an occupancydetector, a humidity sensor, or a carbon dioxide sensor.

In some embodiments, the sleep onset event is determined based, at leastin part, on a predetermined sleep schedule, and the predetermined sleepschedule is based, at least in part, on a historical environmentalsensor input.

In some embodiments, the execution of the sleep profile adjusts thesetpoint temperature such that the temperature of the air in theenvironment leads the occupant in the environment into the sleep stateor the wakeful state by virtue of the sleep profile comprising a firstportion (the first portion decreasing the temperature of the air in theenvironment in advance of an onset of a target sleep period for theoccupant by decreasing the setpoint temperature prior to the onset ofthe target sleep period) and a second portion (the second portionincreasing the temperature of the air in the environment in advance ofan end of the target sleep period for the occupant by increasing thesetpoint temperature prior to the end of the target sleep period).

In some embodiments, the sleep profile further comprises a thirdportion, subsequent to the first portion and prior to the secondportion, the third portion maintaining the temperature of the air in theenvironment by maintaining the setpoint temperature.

In some embodiments, the setpoint temperature is set to a base setpointtemperature prior to the execution of the sleep profile, and thedecreasing decreases the temperature of the air in the environment bydecreasing the setpoint temperature, at an onset of the time period,from the base setpoint temperature to a lower setpoint temperature, overa first period of time comprising one or more temperature decreasingportions.

In some embodiments, the decreasing the setpoint temperature acceleratesa rate of decrease in the setpoint temperature from a first rate ofdecrease during a first one of the one or more temperature decreasingportions to a second rate of decrease during a second one of the one ormore temperature decreasing portions, and the first one of the one ormore temperature decreasing portions precedes the second one of the oneor more temperature decreasing portions in the sleep profile.

In some embodiments, the setpoint temperature is set to a base setpointtemperature prior to the execution of the sleep profile, and theincreasing increases the temperature of the air in the environment byincreasing the setpoint temperature from the lower setpoint temperatureto the base setpoint temperature, over a second period of timecomprising one or more temperature increasing portions.

In some embodiments, the increasing the setpoint temperature acceleratesa rate of increase in the setpoint temperature from a first rate ofincrease during a first one of the one or more temperature increasingportions to a second rate of increase during a second one of the one ormore temperature increasing portions, and the first one of the one ormore temperature increasing portions precedes the second one of the oneor more temperature increasing portions in the sleep profile.

In some embodiments, the target sleep period comprises at least aportion of one of the one or more temperature decreasing portions, thethird portion, and at least a portion of one of the one or moretemperature increasing portions.

In some embodiments, the sleep profile causes the temperature of the airin the environment to be adjusted in a manner that leads the occupantinto the sleep state by virtue of the function emulating a change in abody temperature of a human being before, during, and after sleep.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the disclosed system and method are describedherein with reference to the drawings wherein:

FIG. 1 is a block diagram of an embodiment of an HVAC system having asleep- enhancing thermostat in accordance with the present disclosure;

FIGS. 2A and 2B illustrates a bedside device in accordance with anembodiment of the present disclosure;

FIG. 3 illustrates a sleep profile in accordance with an embodiment ofthe present disclosure;

FIG. 4 is a flowchart illustrating a method of sleep enhancement in anHVAC system in accordance with the present disclosure; and

FIG. 5 is an exemplary user interface of a sleep-enhancing thermostat inaccordance with the present disclosure.

The various aspects of the present disclosure mentioned above aredescribed in further detail with reference to the aforementioned figuresand the following detailed description of exemplary embodiments.

DETAILED DESCRIPTION

Particular illustrative embodiments of the present disclosure aredescribed hereinbelow with reference to the accompanying drawings;however, the disclosed embodiments are merely examples of thedisclosure, which may be embodied in various forms. Well-known functionsor constructions and repetitive matter are not described in detail toavoid obscuring the present disclosure in unnecessary or redundantdetail. Therefore, specific structural and functional details disclosedherein are not to be interpreted as limiting, but merely as a basis forthe claims and as a representative basis for teaching one skilled in theart to variously employ the present disclosure in any appropriatelydetailed structure. In this description, as well as in the drawings,like-referenced numbers represent elements which may perform the same,similar, or equivalent functions. The word “exemplary” is used herein tomean “serving as a non-limiting example, instance, or illustration.” Anyembodiment described herein as “exemplary” is not necessarily to beconstrued as preferred or advantageous over other embodiments. The word“example” may be used interchangeably with the term “exemplary.”

Aspects of the present disclosure are described herein in terms offunctional block components and various processing steps. It should beappreciated that such functional blocks configured to perform thespecified functions may be embodied in mechanical devices,electromechanical devices, analog circuitry, digital circuitry, and/ormodules embodied in a computer. For example, the present disclosure mayemploy various discrete components, integrated circuit components (e.g.,memory elements, processing elements, logic elements, look-up tables,and the like) which may carry out a variety of functions, whetherindependently, in cooperation with one or more other components, and/orunder the control of one or more processors or other control devices. Itshould be appreciated that the particular implementations describedherein are illustrative of the disclosure and its best mode and are notintended to otherwise limit the scope of the present disclosure in anyway. One skilled in the art will also appreciate that, for securityreasons, any element of the present disclosure may consist of anycombination of databases or components at a single location or atmultiple locations, wherein each database or system includes any ofvarious suitable security features, such as firewalls, access codes,authentication, encryption, de-encryption, compression, decompression,and/or the like. It should be understood that the steps recited hereinmay be executed in any order and are not limited to the order presented.Moreover, two or more steps or actions recited herein may be performedconcurrently.

In one aspect, the present disclosure is directed to a sleep-enhancingHVAC thermostat and related systems and methods for inducing andimproving sleep of a person in the temperature-controlled environment.Aspects of the present disclosure utilize techniques which emulate ahuman body's natural temperature decline at the onset of, and during,sleep. The technique causes the controlled environment temperature toemulate the rate and timing of the body's natural decline intemperature, and, in a related aspect, the timing of the environmentaltemperature change leads the body's natural temperature changes, whichfurther helps induce and maintain sleep. In a related aspect of thepresent disclosure, the temperature of the environment is increased atthe end of the sleep period when the body is at its coldest, whichfurther helps avoid disruption of natural sleep patterns that occurtowards the end of the sleep period. In another aspect of the presentdisclosure, the rate of change of the environment temperature is limitedto no more than the rate that will wake a sleeping person, which hasbeen determined to be no more than 0.025° C./minute or 2.7° F./hour. Inyet another aspect of the present disclosure, the thermostat and relatedsystems and methods include determining the onset of a sleep period viaa scheduled sleep time, receipt of a user input, by utilizing currentand historical environmental sensor inputs such as motion, occupancy,and CO₂ levels, and/or by utilizing current and historical physiologicalsensor inputs such as heart rate, body temperature, skin temperature,blood pressure, respiration rate, blood oxygen (SpO₂), and galvanic skinresistance.

In more detail, and with reference to FIG. 1 , an example embodiment ofan HVAC system 1 having a sleep-enhancing thermostat 10 is shown.Thermostat 10 includes, in operative communication, processor 11,touchscreen 12, memory 13, data interface 14, one or more sensors 15,and HVAC interface 16. Sensor 15 may include a temperature sensor,humidity sensor, light sensor, proximity sensor, thermal imaging sensorsuch as an infrared sensor, and/or a motion sensor. HVAC interface 16 isconfigured to communicatively couple thermostat 10 with HVAC equipment20. HVAC equipment 20 may include, without limitation, an outdoor unit21, an indoor unit 22, and/or a furnace 23 which provide conditionedair, e.g., heated, cooled, or dehumidified air, to the controlled indoorenvironment of the home. Data interface 14 is configured to communicablycouple thermostat 10 with other devices, including without limitation asensor device 31, a wearable device 32, a bedside device 33, and/or aremote device 34.

Data interface 14 is configured to communicate using one or more of awireless communication protocol, such as without limitation, any variantof IEEE 802.11 (commonly known as WiFi), variants of IEEE 802.15wireless personal area networking such as Bluetooth® and Z-Wave®, andother wireless standards such as ZigBee®. Data interface 14 may beadditionally or alternatively be configured to communicate using a wiredprotocol using dedicated data lines (e.g., Ethernet) or via powerlinecommunication links using, for example, IEEE 1901, X10® and/or Insteon®protocol.

Data interface 14 may be additionally or alternatively be configured tocommunicate using a wide area cellular mobile network using, for exampleand without limitation, a GSM protocol (3G, 4G, LTE etc.), a CDMAprotocol (EV-DO, SV-DO, etc.), and so forth. In embodiments, datainterface 14 is configured as a WiFi hot-spot or wired router to enablethermostat 10 to provide internet access via the cellular data networkto other internet-enabled devices within the home, such as computers,notebooks, mobile devices, streaming media devices, security devices,appliances, and so forth.

HVAC interface 16 is configured to communicate between thermostat 10 andHVAC equipment 20 using any communications protocol suitable for usewith HVAC equipment 20. For example, and without limitation, whereindoor unit 21, outdoor unit 22, and/or furnace 23 employ single- ordual-speed motors, HVAC interface 16 may include a 24V switched circuitinterface which operates with well-known HVAC color-coded wiring schemes(Rc, Rh, C, Y, W, Y2, W2, etc.). Where indoor unit 21 and/or outdoorunit 22 employ variable-speed motors, HVAC interface 16 may include adigital signaling interface such as, without limitation, CAN bus,RS-485, ComfortLink II™, ClimateTalk™, and the like. In embodiments,HVAC interface 16 may operate using both 24V switched circuits anddigital signaling protocols to flexibly accommodate any combination ofHVAC equipment. In embodiments, any of the functions of data interface14 may be performed by HVAC interface 16, and vice versa. Inembodiments, HVAC interface 16 may be incorporated within data interface14.

Thermostat 10 is configured for communication with one or more remotedevices 34 via network 30 (which may include a LAN, Z-Wave® or ZigBee®mesh network, and/or the public internet). Remote device 34 may include,without limitation, a mobile device, smart phone, a tablet, a notebookcomputer, a desktop computer, smart TV, and/or a touchscreen device.

In some embodiments, outdoor unit 21 and indoor unit 22 may beconfigured as a split HVAC system wherein outdoor unit 21 is configuredas an air conditioner or heat pump unit, and indoor unit 22 isconfigured as an air handling unit. In other embodiments, outdoor unit21 and indoor unit 22 may be included in a packaged system which sharesa common enclosure. In some embodiments, outdoor unit 21 and/or indoorunit 22 may include an auxiliary heater 24 for use when a heat pumpalone is insufficient to meet the heating demand of the home. Furnace 23and/or auxiliary heater 24 provide heat via combustion and/or resistiveelectrical elements.

Thermostat 10 includes a sleep profile 17, a sleep onset determinationmodule 18, and a scheduling module 19. As will be appreciated by one ofordinary skill in the art, aspects of the present disclosure, includingbut not limited to sleep profile 17, sleep onset determination module18, and scheduling module 19, may take the form of an entirely softwareembodiment, an entirely hardware embodiment, or an embodiment combiningboth software and hardware. Embodiments may take the form of a computerprogram product on any suitable non-transitory computer-readable storagemedium having computer-readable program code embodied in the storagemedium. Any suitable computer-readable storage medium may be utilized,including semiconductor storage devices, e.g., mask ROM, EEPROM, flashmemory, USB thumb drives, and the like. Computer program instructionsembodying the present disclosure may be stored in memory 13 or othercomputer-readable memory that can direct processor 11, a computer, orother programmable data processing apparatus to function in a particularmanner, such that the instructions stored in the computer-readablememory produce an article of manufacture, including instruction means,that implement the functions described herein.

Sensor device 31 incorporates one or more sensors that are configured tosense a property of the controlled environment. In an embodiment, sensordevice 31 includes one or more of a motion detector, an occupancydetector, a temperature sensor, a humidity sensor, light sensor, or aCO₂ sensor. The sensed property is communicated to sleep onset detectionmodule 18, which monitors any one, some, or all of these properties toassess the level of human activity within the controlled environment todetermine the onset of sleep. By monitoring motion sensing, occupancy,and/or CO₂ levels in the controlled environment, sleep onset detectionmodule 18 determines the sleeping habits of the home's occupants. Forexample, where sensor device 31 detects an absence of motion inconjunction with a decrease in CO2, sleep onset detection module 18determines that a sleep period has begun, which, in turn, beginsexecution of sleep profile 17.

Scheduling module 19 stores one or more schedules which enablethermostat 10 to vary setpoint temperature at pre-programmed times. In atypical embodiment, includes the capability of following a differentschedule based upon day of week, for example, a weekday schedule and aweekend schedule may be stored in scheduling module 19. Each scheduleincludes a plurality of time/temperature setpoint entries which definethe time at which the associated temperature setpoint is active. Aschedule may be predefined and/or may be editable by a user as desired.In an embodiment, scheduling module 19 includes a time/temperature entryfor morning (wake-up), day (at work), evening (dinnertime) and night(sleep time). The night/sleep time entry may, in some embodiments, beconfigured to act as a sleep onset event, which is communicated to sleeponset determination module 18 to trigger the execution of sleep profile17. Preferably, thermostat 10 is configured to allow sleep onsetdetermination module 18 to trigger the execution of sleep profile 17 inadvance of the night/sleep time entry to enable sleep profile 17 to leadthe user into sleep. In embodiments, thermostat 10 is configured totrigger execution of sleep profile 17 two hours prior to the schedulednight/sleep time.

Sleep onset determination module 18 may additionally or alternativelyreceive user physiological parameters from a wearable device 32 worn bya user. Such user physiological parameters include, without limitation,heart rate, body temperature, skin temperature, blood pressure,respiration rate, blood oxygen (SpO2), and/or galvanic skin resistance.Any one, some or all of the user physiological parameters aretransmitted by wearable device 32 to sleep onset detection module 18,which, in turn, determines the onset of sleep based on the one or morereceived user physiological parameters. For example, if a decrease inrespiration rate is detected alone or in conjunction with a decrease inbody temperature, a sleep onset event is deemed to have occurred andsleep onset determination module 18 causes execution of sleep profile 17to commence.

In embodiments where HVAC system 1 includes a plurality of sensordevices 31 placed throughout the controlled environment, environmentalparameters from throughout the environment are utilized to detect andpredict the onset of sleep. For example, if a family typically gathersin the living room after dinner for three hours before going to sleep,environmental parameters consistent with this activity will detected bythe living room sensor device 31 (e.g., raised CO₂ levels, limitedmotion detected). If this pattern is repeated over several days, sleeponset detection module 18 will begin execution of sleep profile 17 atthe observed time, e.g., three hours after raised CO₂ levels and limitedmotion is detected at living room sensor device 31. In some embodiments,sleep onset detection module 18 will begin execution of sleep profile 17prior to the observed time, e.g., two hours before the predicted sleeptime, to lead the users into sleep.

In embodiments, HVAC system 1 includes a plurality of wearable devices32, each worn by an individual user, that are in communication withsleep onset detection module 18. In these embodiments, sleep onsetdetection module 18 monitors the current and historical physiologicaldata of each individual user to determine the onset of sleep of eachuser, and/or to record and predict the desired sleep time of each user.In embodiments, wearable device 32 includes a unique electronicidentifier that is communicated to sleep onset detection module 18.Thermostat 10 may commence the execution of sleep profile 17 based on acompromise sleep onset time (e.g., the mean bedtime of the plurality ofindividual users). In embodiments where HVAC system 1 includes multiplezone capability, or, for example, the ability to independently adjustthe temperature of each bedroom, multiple sleep profiles may be executedconcurrently to accommodate the sleep schedules of individual occupants.

HVAC system 1 additionally or alternatively includes a bedside device 33that, in the example embodiment illustrated in FIGS. 2A and 2B, isconfigured for attachment to an alarm clock 35, nightstand, lamp,lampshade, or other bedside object capable of providing a suitablemounting surface for bedside device 29. Bedside device 33 includes ahousing 36, power source 37, antenna 38, and an actuator 39, such aswithout limitation, a pushbutton. Actuator 39, power source 37, andantenna 38 are communicatively coupled to a transmitter 40. In use, whena user is ready to turn in for sleep, the user presses actuator 39 whichcauses transmitter 40 to transmit a sleep onset signal to thermostat 10and sleep onset determination module 18 to indicate a sleep onset eventhas occurred. In embodiments, bedside device 33 is configured forattachment to the bed, e.g., mattress, box spring, and/or bedframe tosense the presence of an occupant in the bed by measuring weight,pressure, motion, vibrations and/or sensing changes thereof.

Upon detection of a sleep onset event, sleep onset determination module18 causes execution of sleep profile 17 to commence, and, inembodiments, records the sleep onset event as part of a learningprocess. The sleep onset event may be represented by data items such astime of event, date, and day-of-week. A sequence number and/or a uniqueelectronic identifier may be recorded which enumerates and/ordistinguishes the instant sleep onset event among a plurality of sleeponset events recorded in a given evening. This enables, for example,thermostat 10 to monitor different residents of the household who may goto bed at different times.

As shown in FIG. 3 , an exemplary sleep profile 17 in accordance withthe present disclosure defines a series of sleep-enhancing setpointtemperature alterations. In the FIG. 3 example, the base setpoint 41 isshown to be 72° F. Typically, this would represent the preferredtemperature set by the user. The targeted sleep duration is seven hours,between the hours or 11:00 PM (point 46) and 67:00 AM (point 51). Sleepprofile 17 begins execution at point 42 which, in the present exampleoccurs at 8:00 PM. Note that, in the present example, the execution ofsleep profile 17 leads the time of the desired onset of sleep 46, e.g.,11:00 PM, by three hours.

Upon initial execution, sleep profile 17 enters a first temperaturedecreasing portion 43 wherein the setpoint temperature is decreased 1.0°F. over the course of two hours, e.g., the setpoint is changed at a rateof about −0.5° F./hour. In the present example, the setpoint reaches 71°F. at 10:00 PM (point 44). At point 44, a second temperature decreasingportion 45 is entered during which the rate of setpoint decreaseaccelerates to about −1.0° F./hour for a period of two hours e.g., abouttwice the rate of the first temperature decreasing portion. Note that inthe present example, the desired onset of sleep 46 occurs approximatelyhalfway though second temperature decreasing portion 45, e.g., at 11:00PM. When the second temperature decreasing portion 45 is completed, atpoint 47 a temperature sustaining portion 48 is entered where thesetpoint is held unchanged for four hours. As shown in the FIG. 3example, the setpoint during the temperature sustaining portion 48 isheld at a temperature 3° F. cooler than the base setpoint temperature,e.g., at 69° F. It should be understood that the duration of temperaturesustaining portion 48 may be adjusted, e.g., longer or short than fourhours, depending at least in part upon the desired targeted sleepduration.

At point 49 a first temperature increasing portion 50 is entered duringwhich the setpoint temperature is increased 1.0° F. over the course oftwo hours, e.g., the setpoint is changed at a rate of about +0.5°F./hour. Note that point 49 occurs two hours prior to point 51, the endof the target sleep period. At point 51, a second temperature increasingportion 52 is entered during which the rate of setpoint decreaseaccelerates to about +1.0° F./hour for a period of two hours, e.g.,about twice the rate of the first temperature increasing portion. Atpoint 53, or 8:00 AM, the setpoint has reached the original basesetpoint 41 of 72° F., and the sleep profile concludes.

Turning to FIG. 4 , an example embodiment of a sleep-enhancing method ofoperating an HVAC system 60 is shown. At block 61, events that areindicative of sleep onset are collected from one or more sources, suchas, without limitation, a manual sleep mode selection made at awall-mounted thermostat (FIG. 5 ) or a bedside unit, one or moreenvironmental parameters derived from an environmental sensor, and/orone or more biological parameters derived from a physiological sensor(e.g., a wearable device). The collected events are analyzed in block 62to determine whether sufficient events have been collected to identify asleep pattern within a predetermined degree of certainty. For example,in an embodiment, at least two weeks of sleep onset events are collectedto identify a sleep pattern. In embodiments, the degree of certainty maybe evaluated using any suitable technique, such as without limitation,events occurring within one standard deviation of the mean time ofoccurrence. A sleep pattern may indicate that, for example, on weekdaysthe sleep onset time is 10:00 PM and on weekends the sleep onset time is11:30 PM. If a sleep pattern cannot be identified, the event collectioncontinues at block 61.

If a sleep pattern is identified, then in block 63 the sleep onsettime(s) become active and are entered into an HVAC setpoint schedule. Inblock 64, the HVAC sleep profile is initiated in advance of thescheduled sleep onset time in order to lead the occupants into sleep,and in block 65, the sleep profile is executed as described in detailabove.

FIG. 5 illustrates an example user interface 70 of thermostat 10. Userinterface 70 includes a sleep mode button 71 that may be actuated tomanually enter into sleep mode; a sleep menu button 72 that may beactuated to enter or customize sleep mode parameters, such as, withoutlimitation, the amount of sleep desired (in hours), duration of theaforementioned portions of the sleep profile (in relative or absoluteterms), or modify sleep profile temperatures and/or rates. A sleep stageindicator 73 provides to non-sleeping users visual feedback of thecurrent sleep enhancement status of HVAC system 1. Other UI elements maybe advantageously employed to facilitate user input or feedbackincluding without limitation, voice activation, speech synthesis, asmart phone application, tablet application, smart TV application, anInternet web portal, a motion/gesture sensor, and/or a proximity sensor.

ASPECTS

It is noted that any of aspects 1-20 may be combined with each other inany suitable combination.

Aspect 1. A sleep-enhancing method of operating an HVAC system,comprising determining the onset of a sleep time period and decreasingthe target temperature of the HVAC system according to a temperatureprofile, wherein the temperature profile emulates the change in bodytemperature of a human being during the sleep time period.

Aspect 2. The method in accordance with aspect 1, further comprisingincreasing the target temperature of the HVAC system prior to the end ofthe sleep time period

Aspect 3. The method in accordance with aspect 1 or 2, further enhancingsleep by commencing the lowering prior to the onset of the sleep timeperiod to cause the temperature profile to lead the change in bodytemperature of a human being during the sleep time period.

Aspect 4. The method in accordance with any of aspects 1-3, wherein thetemperature profile defines a plurality of consecutive sub-periods

Aspect 5. The method in accordance with any of aspects 1-4, whereinduring a first sub-period, the target temperature decreases at a firstrate.

Aspect 6. The method in accordance with any of aspects 1-5, whereinduring a second sub-period, the target temperature decreases at a secondrate.

Aspect 7. The method in accordance with any of aspects 1-6, whereinduring a third sub-period, the target temperature remains unchanged.

Aspect 8. The method in accordance with any of aspects 1-7, whereinduring a fourth sub-period, the target temperature increases at a thirdrate.

Aspect 9. The method in accordance with any of aspects 1-8, wherein thedetermining is based on a schedule and/or an occupancy.

Aspect 10. The method in accordance with any of aspects 1-9, wherein therate of change of the target temperature of the HVAC system is no morethan about 0.025° C. per minute.

Aspect 11. A sleep-enhancing controller for an HVAC system, comprising atemperature sensor interface, an HVAC control interface, a processor inoperative communication with the temperature sensor interface and theHVAC control interface, and a memory in operative communication with theprocessor including instructions, which, when executed by the processor,cause the sleep-enhancing controller to determine the onset of a sleeptime period and decrease the target temperature of the HVAC systemaccording to a temperature profile that emulates the change in bodytemperature of a human being during sleep.

Aspect 12. The controller in accordance with aspect 11, wherein theinstructions further cause the sleep-enhancing controller to raise thetarget temperature of the HVAC system prior to the end of the sleep timeperiod.

Aspect 13. The controller in accordance with aspect 11 or 12, whereinthe instructions further cause the controller to commence lowering thetarget temperature prior to the onset of the sleep time period to causethe temperature profile to lead the change in body temperature of ahuman being during the sleep time period.

Aspect 14. The controller in accordance with any of aspects 11-13,wherein during a first portion of the sleep time period, theinstructions cause the controller to decrease the target temperature ata first rate.

Aspect 15. The controller in accordance with any of aspects 11-14,wherein during a second portion of the sleep time period, theinstructions cause the controller to decrease the target temperature ata second rate.

Aspect 16. The controller in accordance with any of aspects 11-15,wherein during a third portion of the sleep time period, theinstructions cause the controller to maintain the target temperatureunchanged.

Aspect 17. The controller in accordance with any of aspects 11-16,wherein during a fourth portion of the sleep time period, theinstructions cause the controller to increase the target temperature ata third rate.

Aspect 18. The controller in accordance with claim any of aspects 11-17,wherein the instructions further cause the controller to determine theonset of the sleep time period based on a predetermined sleep schedule.

Aspect 19. The controller in accordance with any of aspects 11-18,further comprising an occupancy sensor interface in operablecommunication with the processor and wherein the instructions furthercause the controller to determine an occupancy state based on a signalreceived from the occupancy sensor interface and to determine the onsetof the sleep time period in response to the occupancy state.

Aspect 20. The controller in accordance with any of aspects 11-19,wherein the instructions further cause the controller to limit the rateof change of the target temperature of the HVAC system to no more thanabout 0.025° C. per minute.

Particular embodiments of the present disclosure have been describedherein, however, it is to be understood that the disclosed embodimentsare merely examples of the disclosure, which may be embodied in variousforms. Well-known functions or constructions are not described in detailto avoid obscuring the present disclosure in unnecessary detail.Therefore, specific structural and functional details disclosed hereinare not to be interpreted as limiting, but merely as a basis for theclaims and as a representative basis for teaching one skilled in the artto variously employ the present disclosure in any appropriately detailedstructure.

What is claimed is:
 1. A method comprising: determining an occurrence ofan event, wherein the occurrence of the event is determined by acontroller of a heating, ventilation, and air conditioning (HVAC)system, and the HVAC system controls a temperature of air in anenvironment by controlling a setpoint temperature of conditioned airprovided by the HVAC system to the environment; and in response to adetermination that the event has occurred, altering the temperature ofthe air in the environment by executing a sleep profile, wherein thesleep profile is executed by the controller, and execution of the sleepprofile adjusts the setpoint temperature as a function of time over atime period, such that the temperature of the air in the environmentleads an occupant in the environment into a sleep state or a wakefulstate.
 2. The method of claim 1, wherein the determining the occurrenceof the event comprises: receiving a signal at the controller, whereinthe signal is received from a device communicatively coupled to thecontroller, and the signal indicates detection of the event by thedevice.
 3. The method of claim 2, wherein the determining is performedby a sleep onset determination module of the controller, the event is asleep onset event, the signal is a sleep onset signal, the device sendsthe sleep onset signal to the controller upon detection of the sleeponset event, and the execution of the sleep profile is caused by thesleep onset determination module processing the sleep onset signal. 4.The method of claim 3, further comprising: performing a learningprocess, wherein the learning process comprises recording the sleeponset event as a recorded sleep onset event, and the recorded sleeponset event is one of a plurality of recorded sleep onset eventsrecorded as part of the learning process; and updating a schedule,wherein the schedule is updated using a result of the learning process,and the schedule is maintained by a scheduling module of the controller.5. The method of claim 3, further comprising: detecting the sleep onsetevent, wherein the detecting the sleep onset event comprises receivingone or more environmental conditions of the environment from one or moresensors, and determining occurrence of the sleep onset event based, atleast in part, on the one or more environmental conditions.
 6. Themethod of claim 3, wherein the controller is a thermostat, the HVACsystem comprises the device and the thermostat, the device is one of aplurality of devices, and each of the plurality of devices monitors oneor more environmental parameters by virtue of comprising one or more ofa temperature sensor, a humidity sensor, a light sensor, a proximitysensor, a thermal imaging sensor, a motion sensor, an occupancydetector, a humidity sensor, or a carbon dioxide sensor.
 7. The methodof claim 3, wherein the sleep onset event is determined based, at leastin part, on a predetermined sleep schedule, and the predetermined sleepschedule is based, at least in part, on a historical environmentalsensor input.
 8. The method of claim 1, wherein the execution of thesleep profile adjusts the setpoint temperature such that the temperatureof the air in the environment leads the occupant in the environment intothe sleep state or the wakeful state by virtue of the sleep profilecomprising a first portion, the first portion decreasing the temperatureof the air in the environment in advance of an onset of a target sleepperiod for the occupant by decreasing the setpoint temperature prior tothe onset of the target sleep period, and a second portion, the secondportion increasing the temperature of the air in the environment inadvance of an end of the target sleep period for the occupant byincreasing the setpoint temperature prior to the end of the target sleepperiod.
 9. The method of claim 8, wherein the sleep profile furthercomprises a third portion, subsequent to the first portion and prior tothe second portion, the third portion maintaining the temperature of theair in the environment by maintaining the setpoint temperature.
 10. Themethod of claim 9, wherein the setpoint temperature is set to a basesetpoint temperature prior to the execution of the sleep profile, andthe decreasing decreases the temperature of the air in the environmentby decreasing the setpoint temperature, at an onset of the time period,from the base setpoint temperature to a lower setpoint temperature, overa first period of time comprising one or more temperature decreasingportions.
 11. The method of claim 10, wherein the decreasing thesetpoint temperature accelerates a rate of decrease in the setpointtemperature from a first rate of decrease during a first one of the oneor more temperature decreasing portions to a second rate of decreaseduring a second one of the one or more temperature decreasing portions,and the first one of the one or more temperature decreasing portionsprecedes the second one of the one or more temperature decreasingportions in the sleep profile.
 12. The method of claim 10, wherein thesetpoint temperature is set to a base setpoint temperature prior to theexecution of the sleep profile, and the increasing increases thetemperature of the air in the environment by increasing the setpointtemperature from the lower setpoint temperature to the base setpointtemperature, over a second period of time comprising one or moretemperature increasing portions.
 13. The method of claim 12, wherein theincreasing the setpoint temperature accelerates a rate of increase inthe setpoint temperature from a first rate of increase during a firstone of the one or more temperature increasing portions to a second rateof increase during a second one of the one or more temperatureincreasing portions, and the first one of the one or more temperatureincreasing portions precedes the second one of the one or moretemperature increasing portions in the sleep profile.
 14. The method ofclaim 12, wherein the target sleep period comprises at least a portionof one of the one or more temperature decreasing portions, the thirdportion, and at least a portion of one of the one or more temperatureincreasing portions.
 15. The method of claim 1, wherein the sleepprofile causes the temperature of the air in the environment to beadjusted in a manner that leads the occupant into the sleep state byvirtue of the function emulating a change in a body temperature of ahuman being before, during, and after sleep.
 16. A controllercomprising: one or more processors, wherein the controller is configuredto control a heating, ventilation, and air conditioning (HVAC) system,and the HVAC system controls a temperature of air in an environment bycontrolling a setpoint temperature of conditioned air provided by theHVAC system to the environment; and a computer-readable storage mediumcoupled to the one or more processors, comprising program instructions,which, when executed by the one or more processors, perform a methodcomprising determining an occurrence of an event, wherein the occurrenceof the event is determined by the controller, and in response to adetermination that the event has occurred, altering the temperature ofthe air in the environment by executing a sleep profile, wherein thesleep profile is executed by the controller, and execution of the sleepprofile adjusts the setpoint temperature as a function of time over atime period, such that the temperature of the air in the environmentleads an occupant in the environment into a sleep state or a wakefulstate.
 17. The controller of claim 16, wherein the determining theoccurrence of the event further comprises: receiving a signal at thecontroller, wherein the signal is received from a device communicativelycoupled to the controller, the signal indicates detection of the eventby the device, the determining is performed by a sleep onsetdetermination module of the controller, the event is a sleep onsetevent, the signal is a sleep onset signal, the device sends the sleeponset signal to the controller upon detection of the sleep onset event,and the execution of the sleep profile is caused by the sleep onsetdetermination module processing the sleep onset signal.
 18. Thecontroller of claim 17, wherein the method further comprises: performinga learning process, wherein the learning process comprises recording thesleep onset event as a recorded sleep onset event, and the recordedsleep onset event is one of a plurality of recorded sleep onset eventsrecorded as part of the learning process. updating a schedule, whereinthe schedule is updated using a result of the learning process, and theschedule is maintained by a scheduling module of the controller.
 19. Thecontroller of claim 16, wherein the execution of the sleep profileadjusts the setpoint temperature such that the temperature of the air inthe environment leads the occupant in the environment into the sleepstate or the wakeful state by virtue of the sleep profile comprising afirst portion, the first portion decreasing the temperature of the airin the environment in advance of an onset of a target sleep period forthe occupant by decreasing the setpoint temperature prior to the onsetof the target sleep period, and a second portion, the second portionincreasing the temperature of the air in the environment in advance ofan end of the target sleep period for the occupant by increasing thesetpoint temperature prior to the end of the target sleep period. 20.The controller of claim 19, wherein the sleep profile further comprisesa third portion, subsequent to the first portion and prior to the secondportion, the third portion maintaining the temperature of the air in theenvironment by maintaining the setpoint temperature.